ENGINEERING REPORTS. 
15 
under different denominations, extends, almost without interrup- 
tion, the entire length of the two Americas, traverses the coun- 
try from east to west ; but instead of those lofty volcanic peaks, 
which constitute so striking a feature of extensive portions of 
this gigantic chain of mountains, there is a sudden depression 
of the range in its passage across this Isthmus, the continuity of 
the chain being nearly broken at a point directly in the line of 
shortest communication between the two oceans. The Cordil- 
lera here approaches very near the Pacific coast, and its southern 
slope terminating suddenly, extends in nearly a right line for a 
considerable distance in an east and west direction. But on the 
north side, the base of the mountain range, commencing at the 
point of greatest depression, forms an extended curve to the 
northeast on one side, and to the northwest on the other, having 
the concave side turned towards the north. The section of coun- 
try lying to the south of the Jaltepec and Chalchijapa rivers, 
and circumscribed on the east, south, and west by the above 
mountain range, is made up of elevated table-lands, more or less 
broken and divided by low irregular spurs from the main Cor- 
dillera. To the east and west we find a confused mass of moun- 
tains, which, though attaining to but a moderate elevation, cover 
a large extent of country, particularly on the east, where they 
fill nearly one-half the breadth of the Isthmus. The table-lands 
above mentioned comprise an area of about 1400 square miles, 
and are watered by the Jumuapa, Sarabia, Malatengo, Almo- 
loya, and Chichihua rivers, all tributaries to the Coatzacoalcos, 
and streams of small importance, by reason both of their limited 
length and the comparatively small volume of their waters. The 
first four take their rise in the mountains to the west, and the 
last drains a portion of the mountainous districts to the east. 
These streams present through nearly half their length the char- 
acter of mere torrents, and their currents are generally rapid 
throughout their entire course. In their passage through the 
table-lands, they are generally bordered by a greater or lesser 
breadth of rich alluvial bottoms. 
The elevated spurs and ridges referred to, and which traverse 
the country generally in an east and west direction, offer the 
principal obstacles to the construction of a railroad across this 
